Chlorinated polyvinyl chloride (CPVC) is a thermoplastic polymer produced by chlorination of polyvinyl chloride (PVC) resin. CPVC can withstand a wider temperature range and contains more chlorine as compared to PVC. CPVC has an additional free radical chlorination process that adds chlorine to the material and increases its resiliency in terms of conveying hot materials like water.
CPVC has a wide range of applications including pipes used for hot and cold water distribution in residential and industrial use, transportation of corrosive liquids, high tension cable protection pipe and the like.
Conventionally, PVC obtained by polymerization, is filtered and dried; water is added to the dried PVC to prepare a slurry and the slurry is further used for carrying out chlorination reaction. However, the steps of filtration, washing drying and re-slurrying add up to the overall process time and the running cost. CPVC tends to degrade at higher temperatures; additives and stabilizers are used to prevent the degradation of CPVC. Hence, PVC that has got less heat exposure would be preferable for preparing CPVC.
Therefore, there is felt a need for a simple and economic process for preparation of CPVC directly from PVC.